Germany’s biggest-selling newspaper, Bild, ran an open letter signed by 50 prominent Germans on Tuesday calling for an end to what it sees as rising xenophobia, after thousands of supporters of the far-right group Pegida took to the streets in its biggest rally so far against Muslim immigration.

The No to Pegida appeal, which ran on pages 1-3 of the tabloid and at the top of its website, featured figureheads ranging from the former Social Democrat chancellor Helmut Schmidt to the former national football team captain Oliver Bierhoff condemning the protests.

Bild’s deputy editor Bela Anda, wrote in an editorial to accompany the open letter: “They [the signatories] are saying no to xenophobia and yes to diversity and tolerance … We should not hand over our streets to hollow rallying cries.”

Angela Merkel called for people to turn their backs on Pegida in her New Year’s speech, saying the group was “full of prejudice, a chilliness, even hatred”.

Angela Merkel makes her new year speech at the chancellery in Berlin. Photograph: Maurizio GambariniL/EPA

Some Dresden protesters voiced their frustration at Merkel’s condemnation, with one Pegida organiser telling the crowds that her speech amounted to “state repression”.

But elsewhere in Germany, counter-demonstrations for the first time far outweighed the anti-immigrant rallies, with around 30,000 taking a stand against Pegida marches in Stuttgart, Hamburg, Cologne and Berlin.

In Cologne, church authorities turned off the lights of its Gothic cathedral, one of Germany’s most popular tourist attractions, to prevent the protesters using it as a backdrop. The Brandenburg Gate in Berlin, Dresden’s opera house, the Semperoper, the carmaker Volkswagen’s headquarters in Wolfsburg, and numerous museums, public buildings and private homes across the country were also plunged into darkness.

The illumination of Cologne cathedral is turned off in protest at a rally called by Pediga. Photograph: Martin Meissner/AP

Counter-protesters in Dresden – who numbered 4,000 to Pegida’s 18,000 – gathered in front of the state theatre wearing fluorescent safety vests and carrying brooms, in a symbolic act of wanting to rid the city of what they called the “Pegida mindset”.

On Tuesday a leading German civil rights activist called for dialogue between politicians and supporters of the group. Frank Richter, a prominent campaigner in protests that led to the collapse of the East German communists in 1989, offered to hold a meeting in Dresden where he would act as a mediator between Pegida supporters and mainstream politicians, arguing that the protesters’ frustrations and their lack of trust in government must find an outlet in constructive discourse.

“We are clearly dealing here with a whole array of problems,” Richter, the director of the Federal Agency for Civic Education in the state of Saxony, told Deutschlandfunk. “From a lack of understanding in our political system … to a loss of trust in institutions, people don’t feel they’re being listened to enough. They feel they’re being talked down to, they don’t understand the way the asylum law is applied. It all has to be taken very seriously and I can only hope that what has been taking place on the streets will soon find expression in a constructive dialogue.”